1. Field of the Invention
This invention relates to a method for the preparation of high surface area catalysts, particularly Group VIIIA metal-containing catalysts, and to the use of Group VIIIA metal-containing catalysts for the reduction of carbon monoxide to produce hydrocarbons and oxygenates.
2. Description of Art
The desirability of preparing catalysts with a high surface area in order to obtain high activity is well known. A variety of techniques have been previously described for the preparation of metal-containing catalysts and include impregnation, precipitation and ion-exchange. Usually these techniques involve using the catalyst components in an aqueous solvent.
For example, U.S. Pat. Nos. 4,124,629, 2,786,817, 2,776,244 and 2,564,331 describe techniques for preparing catalysts in which metals are precipitated from aqueous solutions of the metal salts.
Of these references, U.S. Pat. No. 4,124,629 describes a process in which an iron-containing catalyst is precipitated by hydrolyzing urea in an aqueous solution of an aluminum salt and an iron salt. U.S. Pat. No. 2,564,331 describes a technique for the coprecipitation of nickel, zirconium catalysts from aqueous solution containing excess carbonate ions. U.S. Pat. No. 2,776,244 describes the preparation of nickel peroxide catalysts by reaction of nickel sulfate with a water soluble inorganic base such as an alkali metal carbonate while the pH is maintained below 9. Finally U.S. Pat. No. 2,786,817 describes the preparation of iron-containing catalysts by dissolving iron sulfate in water and then precipitating the iron with an alkali such as caustic soda solution.
According to the present invention the metal is precipitated from a polar organic solvent employing a precipitating agent having a solubility of between about 1.times.10.sup.-1 and about 1.times.10.sup.-6 moles per 1000 grams of solvent at 25.degree. C. This causes the metal to be slowly or digestively precipitated from solution and the resulting catalysts exhibit higher surface areas than those obtained using previously described techniques, and also require less activation prior to use.